Properties

Label 2.89.aw_ji
Base field $\F_{89}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{89}$
Dimension:  $2$
L-polynomial:  $1 - 22 x + 242 x^{2} - 1958 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.0585349918242$, $\pm0.441465008176$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{57})\)
Galois group:  $C_2^2$
Jacobians:  $64$
Isomorphism classes:  126

This isogeny class is simple but not geometrically simple, primitive, ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $2$
Slopes:  $[0, 0, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6184$ $62730496$ $496593708712$ $3935115128406016$ $31180550303642832424$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $68$ $7922$ $704420$ $62718750$ $5583849988$ $496981290962$ $44231343944548$ $3936588780734014$ $350356402627473860$ $31181719929966183602$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 64 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{89^{4}}$.

Endomorphism algebra over $\F_{89}$
The endomorphism algebra of this simple isogeny class is \(\Q(i, \sqrt{57})\).
Endomorphism algebra over $\overline{\F}_{89}$
The base change of $A$ to $\F_{89^{4}}$ is 1.62742241.arju 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-57}) \)$)$
Remainder of endomorphism lattice by field

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.89.w_ji$2$(not in LMFDB)
2.89.w_ji$4$(not in LMFDB)
2.89.a_acm$8$(not in LMFDB)

Below is a list of all twists of this isogeny class.

TwistExtension degreeCommon base change
2.89.w_ji$2$(not in LMFDB)
2.89.w_ji$4$(not in LMFDB)
2.89.a_acm$8$(not in LMFDB)
2.89.a_cm$8$(not in LMFDB)